Pump



Nov. 6, 1934. E. H. CARRUTHERS PUMP Filed May 19, 1951 2 Sheets-Sheet l 3 j N VENTOR.

' ATTORNEY.

Nov. 6, 1934. E. H. CARRUTHERS 1,979,863

PUMP

Filed May 19, 1951 2 Sheets-Sheet 2 A TTORNE Y.

Patented Nov. 6, T934 UNITED srArEs PATENT OFFICE PUMP Eben H. Carruthers, Ithaca, N. Y. Application May 19, 1931, SerialNo. 538,452

1 Claim. (Cl. 103-174) I This invention relates to improvements in metering pumps of the character designed to be immersed in a sump or tank for pumping a fluid therefrom.

g It is generally the pra tice to remove a fluid from a sump or tank by means of a suction pump having a substantially long intake conduit opening into the fluid, or by means of a pressure pump to which the fluid is supplied by means of a gravity flow. In most cases, these methods are inemcient and necessitate large installations to enable the pumping of the fluid at high pressures, and in a great many instances require initial priming of the pumps.

' In small pumping apparatus, such as, for example, the pumping equipment for an oil-burning domestic furnace or small heat-treating industrial furnaces, there are many disadvantages in the present construction. The cost of such equipment is high and it requires additional valves, piping and fittings, which are a constant source of expense, as well as necessitating frequent manipulation and adjustment by the operator.

Under the present practice, it is impossible to accurately produce and control a uniform volumetric flow of fluid, due to the presence of fluid valves and other restrictions in the fluid circuit, requiring the constant attention of the operator and dependent for accuracy on his skill and diligence. Also, the inertia of the fluid on the intake side of present pumps prevents an accurate volumetric pumping of fluid.

It is a prime object of my invention'to provide a pump of the character designated having the pumping mechanism thereof operable while continually immersed in the fluid being pumped, whereby the pump is self-rpriming and the usual intake conduit from the pump to the fluid sump or tank is eliminated.

A further object is to provide in such a pump, a pumping mechanism having the parts thereof so designed and constructed as to meter and deliver a constant volume of fluid for each pumping cycle at a uniform flow rate and pressure, said rate and pressure being dependent upon the speed of the pump.

Another important object is to provide in such a pump, a pumping cylinder having an intake port of small areaandlength immersed in the fluid to be pumped, thereby providing a small volume of fluid and a minimum inertia effect on the intake side of the pump; andcreating a static pressure head to counteract the said inertia of the fluid in the intake port, insuring a positive and uniform supply of fluid to the pump.

A still further object is to provide a pump of the character stated including a hollow body having a fluid intake opening of large area immersed 6B in the fluid to be pumped, and a pump cylinder having a fluid intake port of small area relatively to the area of said intake opening, thereby reducing thevelocity of the fluid through the intake opening and thus reducing the liability of the fluid tov draw sediment or foreign material into the pump.

My invention may be more readily understood fromthe following description taken in connection with the accompanying drawings, wherein:

Fig. 1 is a vertical sectional view of a sump pump embodying my invention, said section being taken along the line I-I of Fig. 2; and

Fig. 2, a bottom plan view thereof, partly in section.

Referring to the drawings, A designates genorally a sump pump constructed in accordance with my invention, and includes a hollow cylindrical body 2 having the lower end thereof open throughout its entire inner diameter to provide so a large fluid intake opening 3. The upper end portion of the body 2 is preferably closed by means of an integral wall 4 having a central opening 5 for thepassage of a vertical driving shaft 6 therethrough, said shaft being rotatably 35 mounted in said body by means of a bearing 6a mounted in the opening 5 in any suitable manner.

For the purpose of sealing the opening 5, I provide a flanged member or plate '7 bolted or otherwise secured to the wall 4 of the body 2, and having an inwardly extending annular shoulder 8 for carrying the lower end of a shaft casing 9 in the form of a section of hollow tubing. Said casing 9 is preferably secured to the member 7 by means of annular welding, as at 10, thereby providing a seal for the opening 5 of the body.

Formed integrally with the body 2 and extending radially therefrom, I provide a plurality of hubs or bosses 11 having internally threaded openings 12 therein adapted to receive the threaded ends of closure members or plugs 13. Surrounding the openings 12 I provide inwardly extending annular shoulders 14 for engagement by the enlarged head portions 15 of pump cylinders 16. Lead or other gaskets 17 are disposed between the ends of the closure members 13 and the portions 15 of the cylinders.

The cylinders 16 extend radially inward of the body 2 and are provided with central longitudinally extending bores 18, and a plurality of transports 19.

verse fluid intake ports 19 communicating with said bores and the interior of the body 2. At the outer portions of said bores 18 are inclined seats 20 adapted for engagement by outlet valves 21, the latter being operable Within valve chambers 22 disposed in the inner end portions of the closure members 13. Said valves 21 are provided with depending stems 23 adapted to be entered in the cylinder'bores 18 for guiding the valves, said stems having external grooves- 24- forthe passage of fluid therearound when the valvesare.

in open position.

Fluid passages 25 are formed centrally of the:

closure members 13, terminating at their outer.

ends in right-angle discharge ports 26, said ports being threaded to receive fluid discharge pipes27r. Additional fluid passages 28 are provided from the valve chambers 22 to the passages 25to permit the discharge Valve springs 29 are positioned in the passages 25 and. engage the valves '21 to normally maintain the same in closed position on their seats 20'.

Radial pistons or plungers 30 are slidably mounted within thebores 18 of thecylinders, and are provided with bifurcated followers-31 slidablein suitable radial housings or bearings 32, preferably formed integral with the body'2. Cam rollers 33 are rotatably mounted in the bifurcated followers on pins 34 for engagement with an operating cam 35 secured to the lower reduced end portion 36 of the driving shaft 6, as by means of a key 37. Suitable springs 30a may be provided around the cylinders 16 to maintain the rollers 33 in contact with the cam 35 during the rotation thereof.

The driving shaft 6 extends upwardly beyond the body 2 and the shaft casing-9, and is provided with a miter gear 38 for driving said shaft by means of a motor or other power means 39 and a meshing miter gear 40. Said motor 39 is preferably mounted on a base plate 41, which plate is formed witha bearing portion 42 for retaining a shaft bearing 43 therein. A flanged member 44 is secured to the lower side of the plate 41; said member being similar to the member 7 and having the upper end of the shaft casing 9 Welded thereto'as at 45.

As clearly shown in the drawings, the intake ports 19-are of small; area andlength for contain- 1 ing a comparatively small volume of fluid, the

inertia effect of which will be extremely small, especially as compared with the inertia of the column of fluid contained in the-usual substantially long intake conduit on present pumps.

When the pump is immersed in the relatively large volume ofoil or other fluid to be pumped containedin a sump or tank 46,- there will be a static pressure head It created, directly proportioned to the height of the fluid above the intake This static head insures a positive and uniform flow of fluid through said ports during the operation of the pump, and counteracts the aforesaid inertia of the fluid contained in the intake ports.

It is also to be noted that the proportions of the cylinders and pistons are such that a very small volume of fluid will be delivered for each stroke of the pistons. By reason of the positive and uniform flow induced in the manner just described, the' volume of fluid just delivered will be constant for each cylinder for each stroke of its piston.

In other words, since there are substantially no inertialosses on the intake side of the pump, and the volumetric capacity of the cylinders' is of fluid from said chambers,

constant for each pumping stroke of their pistons, the volume of fluid delivered by the pump will be constant for each cycle thereof. The pump of my invention is, therefore, an accurate metering pump, capable of delivering a predetermined constant volumetric flow of fluid.

Due to the small volume of fluid delivered for each cycle of the pump, delivery or discharge pipes of small internal diameter may be employed for carrying the fluid at extremely high pressures. without danger of disrupting the pipes or pump. Said pipes may be connected to a common multiple fitting 49 for delivery into a common discharge pipe 50, which may be extended to the fluid burner or other use to which the fluid" isto be-applied.

As shown and described, the fluid intake opening 3 in the pump casing 2 is of an extremely large area relatively to the areas of the intake ports 19 in the cylinder 16. This area ratio providesfora low velocity flowof fiuidthrough the opening 3, there being a .high velocity flow through the intake ports 19 only. Thus, the intake opening 3 may be successfully screened" by means of ascreen or strainer 47 retained thereover in any suitable manner, as by means of a holding ring or rim 48, and the low velocity flow therethrough materially reduces the liability of the fluid to draw sediment or foreign matter into the pump.

In operating my invention, the-pump is positioned in the manner described and the motor 39 started. The rotation of the cam 35 by the driving shaft 6 will successively operate the pistons 30 to draw in a predetermined volume of fluid from the interior of the body 2 through the ports 19, and discharge the same through the pipes 27 and 50 bycausing the valves 21 to open by the pressure of the fluid, and permit it to pass from the cylinders to the valve chambers 22 and thence throughthe passages 28, 25 and 26.

Since the volume of fluid is constant for each stroke of 'a piston 30, the volumetric flow rate and the pressure of the fluid is dependent upon the speed at which the pump is operated. Therefore, by varying the'speed of the motor 39; the pump; A may be accurately controlled, todeliver a uniform volumetric flow at a desired rate and pressure. In an actual test, it has been found that pressures up to 10,000 pounds per square inch may-be readily attained by this pump without danger or damage, due to the small volume of fluid delivered for each pumping cycle.

By immersing the pump proper in the fluid, as for example, oil, the-necessity of priming is eliminated, and the working parts thereof are provided with continuous lubrication. In addition, therewill-belittle or no audible sound of operation, which; isparticularly advantageous in the employment of such pumps for domestic use, as inv the ,caseuof. oil-burning. furnaces or the likfi.v

Various changes and modifications are contemplated, provided they fall-within the scope of the following claim.

I claim:

In a pump of the character described, a pump casing, comprising a hollow body substantially of bell-shape having a plurality of radial openings in the side wall thereof, closure members'for the radial openings having fluid passages therethrough and valve chambers therein, valves in the valve chambers, a plurality of longitudinally boredcylinders mounted on the body having fluid intake ports of small'area and length thereinlothereof, operating means for the pistons, said bell-shaped body adapted to be immersed in the fluid to be pumped and providing a static pressure head for counteracting the inertia of the fluid contained in said ports.

EBEN I-I. CARRUTHERS. 

